Offers Prepaid Internet Cards In Japan (NASDAQ:AMZN) might be testing out a new product, but not here in the U.S. The internet retailer will be begin offering prepaid internet access for smartphones and tablet computers in Japan.The company plans to sell SIM cards for $25 USD that offer as much as 500 MB of data usage. This offering in Japan means these prepaid SIM cards could appear in the U.S. market very soon. The new product is quite different from the many wireless companies that offer internet access in conjunction with calling contracts.Amazon is relatively flat, up just over a tenth of a percent to $213.35 in early trading.